Communication and posting system



www W1 1941- .L fc. MARSHALL. mum. M246A49 COMMUNICATION AND POSTING SYSTEM Filed pIl 17, 1940 9 Sheets-S1166?a l LNVEN-roRs J. c. MARSHALL M. L. HASELTON BY 774Mo@ ATTNEY m su June U, 1941. J. @MARSHALL Erm.,

COMMUNICATION AND POSTING SYSTEM 9 Sheets-Sheet 2 Filed April 17, 1940 www W 1941 J. c. MARSHALL ETAL COMMUNCATION VAND POSTING SYSTEM Filed April V1'?, 1940 9 Sheets-Sheet 3 OZFmOu Jun@ W 1941 J. Q. MARSHALL. ET A11...

COMMUNICATION AND POSTING SYSTEM Filed April 17, 1940 9 Sheets-Sheet 4 4-TolL|cs-u DR lo l 2 a 5 s a 3 4 5 6 'l a alo le lalsmlslwm B2 1 e 9 lo l2 44 23d-5678910lll2 B3 la la l5 us n R6 I 5678,9l0ll 234567B9l0ll B5 25 26 E l 2B 29 30 lNVENTGRS J. C. MARSHALL BY IVI. l.. HASELTON Filed April 17, 1940 9 Sheets-Sheet 5 DU RELAYS @di @di @mi Noi di www mum Lo O mmm MMU Mm om@ mma N m E WMM n NCL J M BY SECOND DIGIT IDEN-'ZI TIFICATIDN STORAGE AND DECODING RELAYS I`une .17, 1941.

J. @MARSHALL l-:rAL

COMMUNICATION AND POSTING SYSTEM Y9 sheets-sheet e Filed April 17, 1940 ma mmwmv m N n #E mw om m mo. mm

@m m.O mmm mm N June I 7, 1941.

J. C. MARSHALE EI'AL,

COMMUNICATION AND POSTING SYSTEM Filed April 17, 1940 9 Sheets-Sheet 7 INVENTORS J. C. MARSHALL.

BY M l. HASELTON WM-:Y

NN mm ahun@ 17, 1941- .J. c; MARSHALL ETAL COMMUNICATION AND POSTING SYSTEM Filed April 1'7, 1940 9 Sheets-Sheet 8 m1 DE@ @QE DEU@ DE@ @EE @@@E S %EEULEUEQUEUU M m m m M FUEEFEE @EEE DI m M mgm @m@ @EEE m DE@ :55E WEEE@ FIIlIHlL El L n 4 nl a n n 98.7 6/4 32|O /9\ S H N U E D O C 3 4 5 RANGE INVENTORS J,C.MAR5HA| L BY M.| .HASELTON 7H, l M@ ATT RNr-:Y

June17, 1941- J. c. MARSHALL ETAL 2,246,449

COMMUNICATION AND POSTING SYSTEM Filed April 17, 1940 V9 ShBets-Sheetl 9 REMOTE CONTROL RADIO OPERATOR RADIO OPERATOR F OPERATOR IN AIRCRAFT IN AIRCRAFT IG. Il Q Q E KEYBOARD KEYBOARD KEYBOARD TELEPTR, TELEPTR. TELEFTR.

i AUDIO AUDIO SEEKE R I FREQU E NCY I- FREQUENCY RELEASE g I GENERATOR GENERATR RELAYSA RECEIVING Y RADIO RADIO DISTRIBUTOR xTR xTR END OF A Y MESSAGE AUDIO AUDIO R LAY E SB FREQUENCY I RADIO RECEIVER T FREQUENCY FILTER I I FILTER sEEKER I CONTROL I 2-I L3`I RELAYS l REGEIVINCTI RECEIVING TAPE END OF DISTRIBUTOR END OF DISTRIBUTOR REPERF. MEssAGE 1 MESSAGE 1 RELAYSBI TAFE 'RELAYsBz TAPE SEEKER REPERF. REFERF. MECHMS TAPE sEEKER sEEKER XTR RELEASE RELEASE RELAYsAI TAPE RELAYsAa H XTR.' |L L* l CONNEGTING CONNECTING CONNECTING RELAY RELAY RELAY TELEGRAPI-II DISTRIBUTOR PR'NTER 4 DRI FLIGHT IDENTIFICATION DATA STORAGE AND FIX RANGE TENs I UNITs TENsIUNITs DECOD'NG RELAYS L J l j FIx STORAGE FLIGHT PROGRESS INDICATORS ANNOUNCING A LOCAL OPERATOR D m21 LOCALV 9. 9 KEYBOARD Eu 3 4 a 5 4 s e 7 5 I 3 o s O 7 jICONNECTINGI FIX-2 1 R E Y B B1I 3 2 5 4 O e O 5n 5 I 2 o 4 o n5 Eg 4 a e I 5 e s 4 i- IS FIX-3 1 59N 3 s 4 s o 4 o ,a 2mn: I 2 5 I 4 5 s o ,a (an STORAGE INDICATOR l 2 6 4 o 4 o I Ir- GROUPs *c 5| AND 52 O 5 2 O- 2 O O m I RANGE lRELAYs PULsING SEQUENCE E INVENTORS RELAYs MECHANIsM I J. C. MARSHALL.

Patented `.lune 17,1941

' Joseph C. Marshall, B

llaselton, Rye, N. Y.,

register Corporation,

ration of Delaware aldwin, and Merton L. assignors to rThe Tele- New York, N. Y., a corpox Application `Alllil 17, 1940, Serial N o. 330,058 30 Claims. ,(Cl. 177-353) This invention relates to a communication and posting system, for example, for scheduling, d ispatching and the control of airway traffic, and more particularly to a system for transmitting, recording, and posting airport and airway night control information on announcement or bulletin boardsin which the information thus posted may be received from a local transmitter, such as a telegraph keyboard transmitter, or from transmitters remotely situated with respect to the posting and recording apparatus, the last named transmitters being located at ground stations or Within aircraft in night.

In systems now in general use for recording and posting night plans and night progress reports of aircraft and other messages relative to the control of aircraft in night, hereinafter referred to as airway traiiic control systems, it is the general practice to post this information upon bulletin or announcement boards manually by the use of chalk or crayon, one or more attendants being required at the bulletin or announcement boards for this purpose. As is well known, manual methods of posting such a board possess the disadvantage of errors introduced by the posting attendant, non-uniformity of the characters posted and, furthermore, the obscurement of the board by the attendant in posting the same.

More specifically. such systems employ manual posting boards comprising removable slats or cardholders individual to each of the nights posted and to the various marker or nx classifications and which are interchanged in accordance with the expected or estimated time of passage or arrival of aircraft at the various reporting or marker points en route and at the airport. The time sequence of night data posting may be changed from time to time during the progress of the nights as the result of conditions affecting lthe progress of aircraft such as poor visibility,

ice,` sleet, changes in the direction and velocity of the wind. thenecessity for blind landings and other emergency conditions. The `:night progress boards upon which this information is posted comprise section associated with the check points along the various aircraft routes, and the general practice employed is to post the night control The information posted on the cards usually comprises the night designation symbols followed by a section number, ifany, information asto whether the night is bound toward or away from the control station, the airway tramo controls estimated time when the aircraft will pass over or land at each marker point of the night route; the pilots estimated time of traversing each marker point, the time the aircraft actually passes over or lands at each marker point, the expected approach time when the pilot may receive instructions to start his approach to a landing field, proposed altitude at which a clearance has been issued to cross each marker, the altitude at which'the aircraft actually crosses the various markers and the landing sequence number assigned to landings under instrument conditions.

lln addition to the foregoing, certain other information is usually posted on the night progress boards such, for example, as anV indication that a clearance through a marker or nx has been issued, an indication of a night over the airport, an indication of a stop en route and, in expected approach time, indication that an aircraft has been cleared to the airport control tower or range station, that there will be no delay in landing, or that, if a delay is encountered, the degree of such delay is unknown. y

Local communication facilities comprising well known telephone or telegraph equipment are employed toestablish communication between the airline companies dispatch and radio offices, airport control tower or towers, the local communications operator of the airway tranic control, a government regulating bureau, local military operations onicers, if any, and nearby airports. All conversations over these telephones are usually recorded on records by Ediphone cr Dictaphone machines and the records thus obtained are preinformation with chalk or crayon at the t'ralilcv control centers on cards mounted on removable slats or cardholders as previously stated and remove the cardholders from the display board successively in accordance with the markers or nx points traversed by the aircraft in night. The cards thus removed are placed in the nies as a record of the nights.

served for a period of several eradicating the same. In addition to the disadvantages inherent in manual posting systems, errors in the recordV may result from improper pronouncement of the information to be recorded, additional errors may result from the interpretation of the information received over the telephone, and the rate at which the night information may be posted manually on the various night progress announcing boards is necessarily slow.

One of the objects of the present invention is the provision of an automatic posting and recording system in which the foregoing disadvantages are obviated and w ch is adapted to perform satisfactorily all the functions ofthe systems heretofore proposed days or weeks before ornow in general userand in which the circuits employed are relatively simple, with a minimum number of circuits and conins a seeker mechanism suitable 4for use with the invention,

Fig. 2 shows'a keyset in diagrammatic form adapted for vvuse'with the system,

\Flg. 3 isa view, represented diagrammatically,

` of a section of the announcing or bulletin board,

. Fig. 4 shows a receiving distributor controlled by signals received from the transmitting appa-' ratus of Fig. 1,

Another object of the invention is to provide a system of the character disclosed in which a relatively simple transmitting structure is ernployed to control theoperation of a flight progress board over a single channel of communication and to cause the information posted on the board to be recorded automatically by a recording device.

Another object of the invention is the provision of circuit arrangements and parts therefor whereby the information received is selectively posted on a flight progress display or bulletin board under control of signals over an incoming line or communication channel without the intervention of an attendant.

Another object of the invention is the provision of means for controlling the operation of a night progress board from an airplane or other aircraft in ight.-

An additional object of the invention resides in a novel and improved arrangement whereby the posted information is received from a local keyset or from one of a plurality of other channels of communication, as the case may be, in accordance with the time relationship of the signals received over the channels of communication with respect to the operated condition of the keyset.

Another object resides in the provision of a novel and improved arrangement of circuits and parts whereby the orderof appearance. time or sequence of the information posted on the ight display board may be varied at will in accordance with the signals received from the keyset.

Another object is the provision of means for automatically selecting for operation a group of posting devices associated with a desired flight identification number and classified with respect to a plurality of markers or xes regardless of the position of the group of posting devices on the display board.

Another of the objects of the present invention resides in the provision of means for receiving signals comprising information relative to the control of airway traffic over a channel of communication and automatically classifying and postingI the same in accordance with the' results of such classification.

\An additional object is the provision of means whereby a single keyset operation causes the flight information posted by a selected group 'of posting devices tobe transferred to any other group of posting devices and the information posted by the intermediate groups of posting devices to be shifted automatically to certain others of the posting devices in either direction in accordance with the numerical' relation between the selected and other groups Aof devices.

Still other objects, advantages and improvements will -be apparent from the following description taken into consideration with'the accompanying drawings in which,

Fig. 1 is a view, in diagrammatic form, of cerrtain transmitting and receiving apparatus includ- Fig. 5 shows a group of storage and decoding relays'controiled by the distributor of Fig. 4 and certain storage devices for automatically selecting a desired group of posting devices in accordance with the signals received by the receiving apparatus of Fig. 1,

Fig. 6 shows groups of storage devices and associated control relays for changing the sequence A of the information posted on the devices of Fig. 3,

Fig. 7 shows a transmitting distributor for actuating the devices of Figs. 3. and 5 and certain sequence mechanism comprising a rotary switch and a plurality of control relays,

Fig. 8 shows a code suitable for use with the system,

Fig. 9 illustrates one arrangement of the bulletin or announcement board on which the flight control information is posted.

Fig. 10 is a diagram showing the arrangement of the various sheets comprising the system and,

Fig. 1'1 is a diagram showing the complete system.

In general, in a system of the character cornprising the present invention, diagrammatically shown in Fig. 11, the movements of any desired number of aircraft within a given area of a terminal or other ight announcing station are visually posted on a flight progress announcing board, shown in the lower right hand portion of the figure, preferably by means of rotatable indicators" which are arranged in groups, such as the horizontal rows or tiers designated O to 9, each of which groups is identified with a certain flight and is adapted to display the flight identification number and flight information such as the time at which the aircraft passes or reaches a particular location or other marker point, generally referred to in the art as'a fix, and the altitude of the aircraft at the various fix points, the indicators also being arranged in groups corresponding-to the different fix points to which they relate, such as .Fix-i, Fix-2 and Fix-3 illustrated.

Such a flight. progress announcing board, for exampia may be located at an airway traffic conpoints and the altitude which the aircraft are to maintain at such points, are prepared in advance and are posted initially on the iiight progress announcing board by a local operator. Each aircraft in flight, however, may encounter adverse weather or other conditions which necessitate a change in the planned time or altitude of the aircraft at the various marker points, at which time the radio operator in the aircraft thus affected may either telephone or telegraph the con- Acomprising the flight and fix identification and the new information in regard thereto are transmitted automatically to the traffic control station Where they are temporarily stored and decoded and caused to select and operate the proper group or groups of indicators to display the new information. 1

More specifically, at the radio receiving station referred to above, which is'tuned to receive the signals from the aircraft mentioned, the signals are retransmitted automatically over a communication circuit to the tramo control station Where they are stored on a control form, asby a tape reperforator, and automatically retransmitted by tape transmitter to the receiving equipment associated with the flight `progress announcing. board. Each of the tuned receiving circuits of the foregoing radio receiving station has a tape reperforator and tape transmitter associated therewith, and seeker mechanism common to the various tape transmitters is provided for causing the messages stored in the various tapes by the reperforators to be retransmitted in the proper order, each such message being made ready for retransmission by an end-of-message signal that accompanies the message. By means of this arrangement the information posted on the flight progress announcing board may be kept up to date by the signals transmitted by the radio operators of the various aircraft, without the intervention of the local operator.

Instead of having the radio operators in the aircraft transmit the information directly to the traffic control station, this information may be transmitted by a remote control operator located l along the route who either personally observes the progress of the aircraft or receives the flight information from the aircraft in the manner above stated, and retransmits the desired information, as by means of a keyboard teleprinter, over a communication' circuit `to a tape' reperforator which also has a tape transmitter associated therewith for retransmitting the information to the flight' progress announcing board for selecting and actuating the proper indicators. Either method may be employed or both may be ernployed'at the same time if desired, since the seeker mechanism hereinbefore referred to causes-theI messages stored in the various perforated tapes by the signals transmitted from the aircraft and also those transmitted by the remote control oper- `ator to be `retransmitted to the traffic control station in proper sequence and without interfering with each other. The information thus transmitted either by the radio operator in an aircraft or by the remote control .operator referred to above, includes the flight number and alsoa signal corresponding to the proper marker point or fix,

and these signals automatically cause selection or marker points, and also has means for changing the sequence or order of appearance of the various items of infomation thus posted so that if an aircraft either is delayed or is ahead of its planned on any horizontal row in regard to any particular aircraft in any particular ilx group, so that after .the aircraft has passed one or more of the marker points or has landed, or the flight is otherwise terminated, the information which is thus no longer needed may be removed inorder to provide additional room for other flights. The local operator can, with one operation `of the keyboard, cause the remaining items of information in regard to other aircraft to be transferred to new levels, including the level from which the information has been deleted, which transfer with regard to the other aircraft is automatically effected in response to the foregoing operation of the keyboard, and furthermore the order in which the remaining items of information previously have been posted may be caused to remain unchanged.

Also, the local operator readily can reassignv the groups of indicators to different fix designations to provide for expansion or contraction of the number of items which may be posted with regard to each particular marker point, and here again the sequence of the remaining items in any fix group may be caused to remain unchanged, or

. if desired, the sequence or order in which any one or more of the items are posted may readily be changed at will. The seeker mechanism above referred to cooperates with the signals transmitted by the local operator to insure that such signals will not interfere with 4the signals transmitted from the various aircraft or remote control ground stations. Y

In order to provide a permanent record of Athe various items of information received at the central control station from the various aircraft and remote control stations, a recording device such as a telegraph printer is connected in the circuit so that all of the flight designation, fix and flight information represented by the received signals may be printed to provide a permanent 'record of all the flights within the given area, and also to provide a convenient means for checking the in-` formation posted on the indicators. Various other functions which are also provided by the system, such as checking forimproper signa-ls and insuring that the incoming signals select and aotuate the proper group of indicators, are described hereinafter in detail.

Referring now to the drawings. specifically in which like numerals of reference are employed to designate like parts throughout the several views, there is shown on Figs. l to 7 thereof, a complete system according to a preferred embodiment of the invention. Fig. 1 shows a plurality of `teleprinter mechanisms each comprising a transmitting keyboard for generating and transmitting electrical signals in accordance with the information to be transmitted and receiving mechanism for distributing these signals to'reperforating devices controlled thereby. The operation of the reperforator mechanism causes the information received by the distributor to` be stored in a perforated tape associated with each reperforator mechanism. The keyboard teleprinters in the various flight information zones may be situatedpat remote points from the receiving mechanism such, for example, as airline radio ofllces, airport control towers, army and navy flight control headquarters, local airway traffic control communication centers, any point on the B" network, any point on the airway tramo control communication teleprinter network, such as at range stations, radio beaconsv or markers, or the teleprinters may be situated within the aircraft. The teleprinters located -at ground stations are connected to the receiving distributor by a channel of communication such as a telegraph line wire over which the signals are transmitted, as is well known in the telegraph art, by simplex method of transmission although it will be' understood that multiplex transmission may be employed. The teleprinters situated within aircraft are each operatively connected to a radio transmitter carried by the aircraft whereby the pilot or assistant may operate the teleprinter during the time that the aircraft is in flight andthus transmit radio signals which are received by the radio receiving apparatus of Fig. 1 situated at an'y suitable location, the received signals controlling the operation of the distributing and reperforating mechanism to store the received signals on perforated tapes. Each-radio teleprinter has associated therewith an audio frequency generator whereby the audio component of the radio signals transmitted comprises a predetermined frequency associated with each aircraft and diiers, preferably, from the frequency of other aircraft having similar transmitting mechanism.

The radio receiving apparatus comprises a plurality of audio frequency filters, each associated with an aircraft and tuned to the frequency of the audio .frequency generator of the associated aircraft. l

Each lter circuit is associatedwith distributing and reperforating mechanism whereby messages may be received simultaneously from a plurality of aircraft in flight at any time and stored on perforated tapes regardless of whether other aircraft are transmitting messages at the time.

The specific arrangement shown on Fig. l employs a single radio frequency band for a plurality of radio transmitting teleprinters by em ploying suitable audio frequency generators and filters at the transmitting and receiving stations respectively. It will be understood, however, that different radio frequency bandsmay be employed for the different aircraft in flight, in which case the audio frequency generator and filter equipment and circuits will not be required.

Each message received by the distributor mechanism of Fig. 1`is followed by an end-of-message y signal which is stored in the 'appropriate group of relays of Fig. 1 and causes the seeker mechanism to function and start an associated tape transmitter into operation to transmit the received message during a revolution of the disdrawings, are employed to store and decode the message signals stored on the perforated tape,

two groups of these decoding relays being employed to store and decode the identification characters of a desired flight, one group being employed for the marker or fix infomation, one

group for the range and two groups for the digit information.

Fig. 3 shows the announcing or bulletin board, hereinafter referred to as a flight progress board, comprising ten posting spaces or rows of electromagnetic indicator units for posting the identification, time and altitude of each flight or air- .craft respectively. As more clearly shown on Fig. 9, the lflight progress board is divided into marker or fix sections, each section comprising a. plurality of groups of indicating devices. Fix l, for example, comprises the groups of indicating devices of the x posting or levels 1, 8 and 9, x 2 the lgroups of indicating devices of levels 4, 5 and 6 and i'lx 3 the devices of levels 0, l, 2 and 3.

'Ihe specific relationship between the groups of devices and the fix designations is shown on Fig. 9 by way of example only in order that a clear understanding of the system may be obtained without unnecessary duplication or complication of the circuits and descriptive matter herein,`

board and a greater or lesser number of groups of indicating devices within the different fix sections. Fig. 3 also shows a pair of gang relays associated with each posting space as, for example, the relays G9 and GA9 associated with the posting space 9. The purposeof these relays willbe more clearly apparent as the description proceeds.

The identification ,indicators associated with each posting space are each provided with a set of equally spaced contacts corresponding in number to the number of positions to which the indlcating elements may be moved and arranged 1n a continuous series. A wiper armis attached to the indicator drum assembly and engages the contacts of the indicator in accordance with'the setting of the drum, for example, if the drum is set to display the digit I, the wiper will be in engagement with contact l; similarly, if the indicator is set to its blank position the associated w1per will be in engagement with its contact BL. l 'I'he Wiper and contact assemblies herein referred to are illustrated schematically in arcuate form on Fig. 5 of "the drawings to show more clearly the electrical circuits connected thereto.

It willbe readily apparent, however, that these wipers take' settings in accordance with the settings of their associated indicators in accordance with the aight identicauon symbols posted on' the progress board. There is also shown on Fig. 5, .to the right of these identification wiper assemblies, a group of fix storage indicators designated FSO to FSS which are employed for storing information regarding the fix or marker section of the flight progress board within which a desired group of flight indicators is disposed. .The purpose and function of these x storage indicators will be set forth more in detail as the description proceeds.

T here is shown on Fig. 6 of the drawings, two

groups of storage indicators designated SI and S2 having associated therewith the gang relays MI Ai and M2, A2 respectively and a group of range relays designated IDENT, TIME and ALT for selecting for operation the corresponding indicators of a particular night within a desired x ysection of the flight progress announcing board. Fig. 6

group of sequencev and control relays including y transfer `relays employed for the purpose of changing the sequence or order in which the information appears on the iiight progress board, hereinafter referred to as sequencing. The Vcircuit arrangement shown provides a system which is extremely flexible and in which the sequence operations are automatically accomplished by a single operation of the keyset of Fig. 2.

Fig. 2 shows a keyset comprising a group of fix keys and groups of keys designated HORIZ. POS., CHANGE POS., DATA TENS and UNITS respectively, There is also provided a group of keys designated FS, SEQ, WO, IDENT, TIME and ALT, each of the keysin this group being arranged to remain in the operated position until released by the operation of the key release magnet KR. The keyset is located at the airway traffic control center or within the airport control tower, as the case may be, and preferably in aposition such that the keyset operator is enabled to include the indicators of the fiightprogress board within his field of vision. The keyset is employed for setting up signals controlling the transmission of a message tion posted, as for example, transposing the infor` mation posted on two adjacent rows of indicators or transferring the information posted on a row of indicators to the indicators of any other row and shifting the information posted on the intermediate rows of indicators, without disturbing the order of the intermediate information, either up- L wards or downwardsinaccordance with whether the information taken out of the first order of appearance on the flight progress board is to be transferred to a higher or lower level. This operation is referred to herein as sequencing. In addition to the foregoing, the keyset is employed to wipe out the display on the indicators of the flight progress board. The performance of any of these keyset operations includes the operation of one of the keys FS,Y SEQ, WO, IDENT, TIME and ALT which causes the seeker of Fig. 1 to come to rest on a set of `terminals associated with the keyset and start the distributor 'DRZ in operation to cause the selected indicators to take their new settings to post the desired flight information in the selected posting spaces.

From the foregoing, it will be noted that posting signals'may be received from` a keyboard transmitter located at a ground station at a distance from the receiving station, from an aircraft in flight, and from a local keyset. Means are provided at the receiving station for storing these signals until a seeker mechanism has operated to cause the stored rignalsto be effective in causing the information represented thereby to be posted on the flight progress board Posting the board by incoming signals y The manner in which signals received from the teleprinter I, Fig. 1, over the line L are employed airport from his keyboard teleprinter I located. l' for example, at the Camden ilx or marker point,

information that the flight 34 is scheduled to pass` over the Camden fix at 1:35 P. M. at an altitude 'of 4500 feet which information will be printed on the multiplex printer MP and posted on the flight progress announcing board at the Washington airport. l

The operator at Camden actuates the keys of his teleprinter keyboardin the following order: 3 4 I 3 3 V5 spacespace 3 4 I 2 4 5 t. The first two' keys 3 and 4 of the keys depressed represent the flight identification number, the third key I, the

fix number, corresponding to Camden, the fourth key 3, the range TIME, the fifth and sixth keys 3 and 5, the tens and units digits respectively ,of time and the two operations of the space bar represent a spacing signal between the first and sec- Y is known in the art as a 2B printer that records the signals on a tape in response to start-stop or simplex type signals, such signals being eomposed of marking and spacing line conditions comprising a start impulse followed by groups of permutations of five intelligence impulses in various combinations representing the characters to be transmitted or received and each groupr being terminated by a rest impulse which is of opposite line condition to that of the Start impulse. The actuation of any of the keys' of the associated keyboard causes the transmission of` signals representing the `character assigned to each key.

The operation of the flight identification key 3 causes a start impulse to be applied to the line L, 'thereby setting the distributor 2 into oper- 4 ation. This impulse is followed by a five unit code permutation signal having the code unit I thereof marking and the code units 2, 3, 4 and 5 spacing in character, Fig. 8, followed -by a rest impulse.

The operation of the distributor 2 causes the code units I, 2, 3, 4 and 5 of the intelligence vsignal to be transmitted to the tape reperforator 3 over the conductors 4, 5, 6, 'I and 8 respectively. When this has been accomplished animpulse is transmitted by the distributor over conductor 9 to cause the reperforator to peforate the tape I I issuing therefrom in accordance with the signals received and4 step the tape ahead into position for the fnext succeeding perforating operation correspondingto the second digit of the flight identification number. Since the permutation signal for the digit 3 has the code unit I only marking in character, conductor 4 is energized andrconductors 5, 6, 1 and 8 are deenergized thereby causing a single perforation corresponding to the code unit I to be made in the tape at this time.

Conductors 4, 5, 6, 1 and 8 are connected by way o'f conductors I, 2, 3, 4 and 5 of cable I2 to the'windings of the end-of-message 4relays EMI, EMZI EM3 and EM4, conductors I and 2 of cable I2 being connected to the windings of relay EMI and conductors 3, 4 and -5 of cable I2 being connected to the windings of the relays EM2, EM3 and EM4 respectively. Energization of conductor 4 causes relay EMI to operate by way of conductor I -of cable I2. Relay EMI locks by way of its make contact and armature I3 to battery on conductor I44 supplied by the break contact of the sixth pulse relay 20 of the distributor 2. The operation of relay EMI is with-- out efl'ect at this time, relay EMI releasing upon the subsequent operation of the sixth pulse relay.

In a similar manner the signals corresponding to the dfg'its4, I, 3, 3 and 5 are received and stored/'fin the perforated tape II, the relays EMI to EM4 operating in code combination each time a' digit signal is received. -The two space signals immediately following the digit 5 signal cause the tape to be stepped ahead twice without perforating intelligence signals therein. Signals corresponding to the digits 3, 4, I, 2, 4 and 5 respectively follow the space `signals and are stored in the tape II and also cause the opera.- tion of the end of the message relays EMI to EM4 in code combination corresponding to each of the digitsstored in the tape.

Immediately following the signal for the digit n l 5 is the end-of-message signal which, in the assumed example, is the signal for having code units I, 2 and 4 spacing and units 3 and 5 thereof marking in character. This signal causes relays EM2 and EM4to operate and lock to battery on conductorv I4 and relays EMI and EM3 to be unoperated. Ground at armature I5 and break contact of relay EMI `is extended to armature I6 and make contact of relay EM2, armature I1 and break contact of relay EM3, armature I8 and make contact of relay EM4 and thence by Y thereby applying ground to the locking circuit of the relay L and holding relay L operated.

The operation of relay L at its armature 21 linterrupts the circuit to terminals 3 and 1 of the bank A of the seeker switch and at the make contact of armature 21 of relay L applies ground to the corresponding armatures 21 of the relays K, RI and R2 and thence by way of the break contact of relays K, RI and R2 to terminals I, 2, 4, 5, 6 and 8 of bank A of the' seeker switch'. If it be assumed that the switch wipers are resting on their terminals I at this time, ground at terminal I is extended by way of the switch wiper of bank A, break contact and armature 28 of the seeker stepping magnet SSM and thence to battery, thereby causing the stepping magnet to operate on self interruptions and advance the wiper A thereof to lits terminal 3 which yhas ground removed therefrom bye the operation of relay L.

Witli the wipers of the switch .SSM resting on then@ terminals 3, a circuit is completed from. battery at armature 23 and make contact of relay L, conductor 3|, winding I of relay TC, conductor 32, terminal 3 of bank C of the seeker switch and wiper thereof, conductor 34, winding of the start'magnet SMI of the distributor DRI. Fig. 4, conductor 35, segment I of the ring RI of the distributor DR2, Fig. 6, brush DBI to grounded ring R2, thereby causing relay TC to operate and connect the transmitting tongues of the tape transmitter 26 to the selection magnets of the multiplex printer MP and to the distributor DRI. Relay TC locks from battery by way of its winding 2 and contacts 31, conductor 38, break contact and armature 39 of relay REL, Fig. '7, to ground.

The start magnet SMI operates in series with relay TC thereby attracting the latch 4I and setting the distributor DRI into operation. The' engagement of brush BI of the distributor DRI with segment 2 of ring RI closes a circuit from tongue I of the tape transmitter 26, also designated TTRI, contacts 42 of relay TC, conductor I of cable 43, segment I of ring R2 of the distributor DRI, brush BI, segment 2 of ring RI, conductor I of cable 44, Winding of relay III to ground. Since, in the example assumed, the first digit of the night identification number is the digit 3, the transmitting tongue I of thetape transmitter TTRI is in the closed position, thereby applying battery through resistance 45 to the circuit just described and causing relay III to operate. Relay III locks by way of its contact and armature 46, conductor 2 of cable 41, break contact and armature 48 of release relay REL and thence to ground.

The engagement of segment 2 of ring R3 o1 the distributor DRI by the brush B2, closes a circuit from the tongue 2 of the tape transmitter TTRI Athrough contact 49 of relay TC, conductor 2 of cable 43, segment I of ringR4, brush B2, segment 2 of ring R3, conductor 1 of cable 44 .to the winding of the rst digit identification relay II2. .Relay II2 does not operate, however, as the tongue 2 of the tape transmitter is prevented by the tape II from engaging its transmitting contact. In a similar manner circuits are compl'eted from tongues 3, 4 and 5 of the tape transmitter 'I'IRi by way of conductors 3, 4 and 5 of cable 43, brushes B3, B4 and B5 and their associated segments 2 of rings R5, R1 and R9, conductors I3, I9 and 25 of cable 44 to the windings of relays II3, II4 and |15 respectively. These relays are prevented from operating at this time by the tape II maintaining the tongues 3, 4 -and '5 of the tape transmitter disengaged from their associated contacts. The digit 3 has now been transferred from the perforated tape II to the group of first digit identication relays III to |15 and stored` therein under control of the release relay REL.

As the brushes of theI distributor DRI are disengaged from segment 2 of rings RI, R3, R5, R1 and R9, the circuits between the tongues of the tape ,transmitter TTRI and the group of rst digit identification storage relays are interrupted. As segment 2 of ring RII of the distributor DRI is engaged by the brush B6, battery at segment 2 of ring RI2 is applied by way of brush B6, segment 2 of ring RII, conductor 6- of cable 43, contact 5I of relay TC .to the tape step magnet TS of the tape transmitter TI'RI, the `circuit continuing through resistance 52 to Aground thereby causingthe tape step magnet TS to operate and step the tape perforations corresponding to the second identificationl digit 4 into alignment with the ieeler pins associated with the tape transmitter tongues.

It will be noted that conductors I, 2, 3, 4 and 5 5 of cable 43 are extended to the selection magnets SMI, SM2, SM3, SM4 and SM5, respectively, the opposite end of the windings of these selection magnets being connected to` ground. Withthis arrangement the operation of the tape transmitter tongue I in response to the rst digit 3 of the night identification number causes the selection magnet SMI of the multiplex printer MP to operate in parallel with relay III.

The engagement of segment 2 of the ring RII i5 by the brush B6 applies battery to conductor 6 of cable 43 extending to the print magnet PM of the multiplex printer, the circuit continuing to ground thereby causing the print magnet PM to operate and the printer to record the digit 3. When the bush B5 moves oiI segment 2 of ring RII, battery is removed from conductor 5 of cable 43 and the print magnet PM and tape step magnet TS release. A

As the brushes of the distributor DRI move into engagement with their, segments 4 of rings RI, R3, R5, R1 and R5, the tongues of the tape transmitter 'IIRI are connected by way of conductors 2, 8, I4, 2B and 2B of cable 44 to the windings-of the second digit identification storage relays 2II to 215, Fig. 5. This group of storage and decoding relays is identical Withfthe iirst digit relays III to II5 and for this reason are indicated in diagrammatic form by the rectangle 30.- Reierring to Fig. 8 it will be noted that the 35 digit 4 corresponding to the second digit of the lidentiiication number has the code units 2 and 4 marking and units I,` 3 and 5 thereof spacing in character. The tongues 2 and 4 ot the tape transmitter TTRI will, therefore, bein engage- 40 ment with their associated contacts and apply battery to conductors 2 and 4 of cable 43 extendingto rings R4. and R8 and thenceby way of brushes B2 and B4 to segment 4 of rings R3 and R1, conductors 8 and 20 of cable 44l to cause 45 the associated second digit storage relays 212 and 214 to operate and lock to conductor 2 of cable 41 to which battery is applied by armature 48 'and break contact of relay REL. The second digit 4 is now stored in the storage and decoding 50 relays ZI of Fig. 5, the selection magnets SM2 and SM4 of the monitor printer operating at this time to store the digit 4 within the printer.

As brush B6 of the distributor DRI moves into engagement with segment 4 of ring RII, 55 battery at ring RIZ is applied to conductor 6 of cable 43 to cause the operation of the print magnet PM of the printer and the tape step magnet TS of the tape transmitter TTRI, thereby printing the digit 4 and advancing the tape II 60 whereby the next group of tape perforations corresponding `to the Fix digit I are brought into operative `engagement with the feeler pins of the tape transmitter.

As segment 6 of rings RI, R3, R5, R1 and R9 65 are engaged by their respective brushes, battery is applied to conductors 3, 9,- I5 and 21 of cable 44 thereby causing the operation of fix relays FI, F2, F3 and F5 to store the x digit I now set up by the tongues of the tape transmitter 70 TTRI. 'Ihese fix 4relays lockby way of their contacts and armatures 53 to battery on conductor 2 of cable 41. The engagement of segment 6 of ring RII by the brush B6 applies battery to conductor 6 of cable 43 thereby caus- 75 ing the miiltiplx printer to print the digit I set `up therein by the selection magnets SMI, SM2,

SM3 and SM5 which operated in parallel with the fix relays FI, F2, F3 and F5, respectively. Battery on conductor 6 of cable 43 causes the tape II to be stepped ahead with the code combination 3 corresponding to the range 'IIME in alignment with the feeler pins of the transmitter. This signal has thel code unit I marking and the units 2, 3,\4 and 5 thereof spacing in character, Fig. 8. N

The engagement of segment 8 of the distribu` tor rings by the brushes BI to B5 applies battery to. conductor 4 oi4 cable 44, thereby operating range relay RI which locks by way of its armature to conductor 2 of cable 41 thereby storing the range signal TIME in the range decoding relays. The selection magnet SMI is also operated to store the digit signal within the telegraph printer MP. When brush B6 engages segment 3 of ring RII the digit 3 corresponding to the range 'IIME is printed by the multiplex printer and the tape I I is stepped ahead to the tens data position.

The tens digit 3, it will be recalled, has the code unit I marking and the code units 2, 3, 4 and 5 spacing in character and battery is applied, therefore, by the tape transmitter, to conductor I only of cable 43. When brush BI engages terminal I0 of the ring RI, battery is applied to conductor 5 of cable 44 thereby operating relay DTI which locks by way of its armature 54 to battery on conductor 2 of cable 41. The selection magnet SMI ofthe printer is also operated to store the tens data digit 3. When segment I0 of ring RII is engaged by brush B6, battery on conductor 4E of cable 43 causes the printer to record the digit 3 corresponding to the first digit of the time information and the tape II to be stepped ahead to the data units position.

With the data units digit 5 in position within the tape transmitter TTRI, battery is applied to conductor 5 of cable 43 by the transmitter 'tongue 5 thereby causing the operation of the printer selection magnet SM5. When brush B5 engages segment I2 of ring R9 battery is appliedto conductor 30 of cable 44 extending to the units digit relay DU5, causing relay DU5 to operate and lock to battery on conductor 2 of cable 41. The units digit relays are similarl in all respects to the tens digit relays DTI to DT5 and for this reason are indicated in diagrammatic form by the rectangleV 44 extend to the windings of relays DU2, DU3,

DU4 and DU5 respectively, each of these relays upon operation locking to battery at the break contact and armature 48 of relay REL by way of conductor 2 of cable 41.

When brush B6 engages segment I2 of ring RII, the digit 5 is printed by themultiplex printer and the tape I I is stepped ahead. In the assumed example, it will be recalled, the time data 3 5 is followed by two space signals and, therefore, none of the conductors I to 5 of cable 43 are now connected to battery except conductor 3 which causes the operation of the selection magnet SM3 of the multiplex printer to store the space signal therein.

The signals for the iiight identification num-- ber 34, x I (Camden), time range 3, and time digits 3 5 are now stored in the groups of relays of Fig. 5 and printed on the printer MP. The manner in which these stored signals control the selection and` operation of the time `indicator described.

with ight number 34 and actuatethe same to post the stored time infomation will now be Referring now to Fig. 9 of the 4, drawings, the

I flight number 34 is shown posted in positions -or levels 8, 6 and 3 associated with the Fix sections I, 2 and 3l of the flight progress board, these Fix sections in the example assumed corresponding to Camden, Baltimore and Washington Airports respectively. The time indicators for the flight 34 associated with the Camden Fix I are located in position8. As the distributor brushes BI and B2 pass over segments I3 to 22 of rings RI and R3, a circuit is closed in part, to each of the gang relays GAII and GAI to GA9 successively until thegang lrelay associated with the desired group of indicators is selected. More specifically, when the brush BI engages segment I3 of ring RI, a circuit is closed in part to operate the gang relay GAO and when brush BI engages segment I4 of ring RI a circuit is closed in part to operate the gang relay GAI and as each succeeding segment of ring RI is traversed by the brush BI, circuits GA3, GA4, GAS, GAG and GAT.

When brush B6 passes 01T segment I4 of ring Rl I, ground is removed from conductor 19 thus releasing Athe start magnet SM2 and causing the brush DBI of the distributor DR2 to come to rest at the completion of one revolution thereof.

As brush DBI engages segment 2 of the distributor DR2 ground is applied to conductor 82 extending to the winding of relay ST, thereby causing relay ST to operate. When brush DBI leaves When the brush BI engages segment 2| of the l ring RI, relay GA8, Fig. 3, associated with the indicators 4of position 8 of the flight progress board, is operated over the following circuit: Grounded armature 56, and make contact of relay III, armature 51 and break contact of relay |12, armature 58 and break contact of relay |103, armature 59 and break contact of relay |I4, armature 6| and break contact of relay |15, conductor 3 of cable 62, terminal 3 and wiper of indicator ITB of position 8, conductor 8 of cable 63, segment 2| of ring RI of the distributor DRI, brush BI, segment I0 of ring R2, conductor 8 of cable 64, wiper of indicator unit IU8 of position 8 and terminal 4 thereof, conductor 4 of cable 65, and thence through breakcontacts of second digit identification relays I, 3 and 5 and make contacts of secnd digit relays 2 and 4, conductor '66, armature 61 and make contact of fix relay FI, armature 68 and make contact of relay F2, armature 69 and make contact of relay F3, arma ture 1I and break contact of relay F4, armature 12 and make contact of relay F5, conductor I of cable 13, terminal I and wiper of fix storage indicator FS8, conductor 8 of cable 14, segment 2| of ring R3, brush B2, segment I0 of ring R4,

battery. Relay GA8 locks by way of its contact 16, conductor 11, contact 18 of Vrelay TC, 'conductor 38, break contact and armature 39 of relay REL to ground.

When brush B6 engages segment I4 of `ring RI I, ground at segment 4 of ring R|2 is applied by way of brush B6, segment I4 of ring RII, conductor 19 to the winding of start magnet SM2 of distributor DR2,`the circuit continuing to battery, thereby causing the start magnet SM2 to operate and withdraw the latch 8| from the path of the brush DBI and thus set the distributor DR2 into operation. Segment I4 of ring R|| is of sumcient length to insure that the brush DBI of, the distributor DR'2 has moved out of engagement with segment I of the-ring RI, thereby removing ground from conductor and causing the release of the start magnet SMI of the distributor DRI before the distributor DRI has completed its revolution, whereby-the latch 4| releases and arrests the brushes of the distributor DRI at the completion of their revolution.

, conductor 8 of cable 15, winding of relay GA8 to I segment 2 of the ring R I, relay ST releases. When the brush DBI engages segment 4 of the ring RI,

battery is applied to conductor extending to break contact of relay R3, armature 86 and break contact of relay R4, armature 81 and break contact of relay R5, conductor 6 of cable 88 extending to the winding of the range relay TIME thereby vcausing relay TIME' to operate and select the time indicators of the posting board for operation in accordance with the particular level or position y of these indicators controlled by the selected gang relay GA which, in the assumed example, is the gang relay GAB.

With relay P1 perated in response to the engagement of segment 4 of the ring RI by the brush DBI, a circuit is closed from battery at armature 89 and break contact of relay AG, conductor 4 ofl cable 9|, make contact and armature 92 of relay P1, conductor 93, make contact and armature 94 of' relay TIME, conductor 95, winding and switch contact 96 of indicator TF8, conductor 3 of cable 91, contact 98 of relay GAB, to ground, thereby operating the indicator IU8 in response to the first restoration impulse applied thereto. The indicator TU8 also receives a restoration impulse at this time over the following circuit: Battery at armature 99 and break contact of relay AG, conductor 4 of cable 0|, make contact and arma-y ture |02 of relay P1, conductor |03, make contact Vand armature |64 of relay TIME, conductor |05,

winding and switch contact |06 of indicator TU8, conductor 4 of` cable 91, contact |01 of relay GA8 to ground. As brush DBI moves off segment 4 of the ring RI, pulsing relay P1 releases and at its armatures 92 and |02 interrupts the restoration impulse to the indicators TTB and TU8 respectively, thereby stepping the indicators Aahead one step towards their blank or home positions by this restoration impulse.

Nine additional restoration impulses are transmitted by the relay P1 as the distributor brush DBI engages segments 6, 8, I0, I2, I4, I6, I8, 20 and 22 of the ring RI thereby causing theselected indicators TT8 and TU8 to be restored from their previous settings to their`blank positions, each of the indicators being unresponsive to additional restoration impulses, if any, when in'the blank position due t'o the interruption of their pulsing circuits by the switch contacts 96 and |06 respec- Hicks and Merton L. Haselton, whereas the flight identification number and x storage indicators are of a general type disclosed in Patent 2,155,825 for Numerical comparator, granted April 25, 1939 to Merton L. Haselton and Raymond M. Hicks.

When thebrush DBI engages segment of ring RI, ground is applied to conductor I of cable |09, extending to the winding of relay RSE, Fig. 1. Relay RSS does not operate at this time, however, as the end-of-message signal `perforatedin the tape has not yet been received by the seeker release relays RSI to RS4.

V As brush DBI moves into engagement with segment 1 of ring RI, ground isapplied to the winding of relay PTR causing relay PTR to operate and at its armature I I I and make contact thereof, apply battery to conductor 2 of cable |09 extendingto the print magnet PM of the multiplex printer. Since, as will be recalled, the selection magnet SM3 thereof operated to store a space signal within the printer, the operation of the print magnet merely creates a space in the printed message. As the brush passes off segment 1 of the ring RI, relay PTR and the print magnet release. It will be noted that conductor 2 of cable |09 is connected to conductor 8 of cable 43, thereby causing the tape step magnet TS of the tape transmitter TTRI to be operated in parallel with the print magnet of the printerand step the tape ahead to its next position within the tape Y transmitter.

When brush DBI engages segment I3 of ring RI, ground is applied to the winding of the relay SP, causing it to operate and at its armature ||2 and make contact thereof apply battery to conductor 3 of cable I09and thence to the selection magnet SMS of the printer to'insure that a space` signal will be stored therein. When brush DBI moves off segment I3 of the ring RI, relay SP releases and as the brush DBI moves into engagement with segment I5 of the ring RI, relay PTR again operates causing the printer to insert a second space within the message printed and the tape transmitter to step the tape lahead to the next position corresponding to the first digit of the flight identification number which is now in position to be transmitted by the tape transmittel.

When the brush DBI passes off. segment I5 of the ring RI, relay PTR releases and removes battery from conductor 2 of cable I|l9y thus causing the release of the print magnet and the tape step magnet. As segment 24 of thering R2 is traversed by the brush DBI, ground is applied to conductor I3, winding of relay AG, from whence the circuit is continued by the way of conductor IIII, break contact and armature II5 of relay SEQ to battery. Relay AG operates and -locks by Way of its make contact and armature II6, conductor I of cable 41, break contact and armature II1 of relay REL to ground. 'I'he operation of relay AG at its armatures 89 and 99 removes battery from conductor 4 of cables 9| and |0I respectively and at its armatures ||8, I|9, |20, |2I, |22 and |23, applies ground to conductors I to 8 of cable |24 extending tocontacts of relays G0 to G9. Relay AG at its armature |25 and make contact thereof applies ground to conductor |26` extending to contact |21 of the gang relays GAI) to GA9. This circuit is continued through operated contact |21 of relay GAB to the winding of relay G8 causing relayG8 to operate and at its contacts |28 to ,|33 close circuits by Way of conductors to 6 of cable |34 to the windings of Y the indicators of the level 8, these circuits being connected to ground at operated contacts of the relay AG, thereby to condition the indicators of.' level 8 for operation by actuation impulses received from the group of pulsing relays PI, P2, P4 and P1, as the distributor DRZ continues itsoperation. The manner in which these circuits are employed to cause the time indicators 'ITB and TUB to be actuated from their blank settings to display the digits 3 and 5 respectively will not be described.

As the distributor brush DBI passes over the group of segments to 44 of the ring RI, a single impulse may be generated from relay PI, two impulses from relay P2, four impulses from relay P4 and seven impulses from relay P1. If an indicator is to be set to display the digit I, the relay PI only is employed, if the digitl 2 is to be displayed relay P2 only is employed, relays PI and P2 being employed to display the digit 3. The digit 4 is selected for display on an indicator by the relay P4, the digit 5 by the relays PI and P4, the digit 6 by relays P2 and P4. When the digit 1 is to be displayed, relay P1 alone is employed. The digit 8 is obtained from a combination of impulses received from relays PI and P1, the digit 9 from relays P2 and P1 and the digit 0 from the relays PI, P2 and P1. In the example assumed, the tens and units of the time infomation to be displayed correspond to the digits 3 and 5 respectively. The setting of the time tens indicator TT8 to display the digit 3 will rst be described.

Referring noW to Fig. 5, the settings of the relays DTI, DTZ, DT3, DT4 and DT5 in response to the digit 3 establishes circuits from battery at the armature of relay DTI by way of conductors I and 2 of cable 9| to pulsing contacts of relays PI and P2 as follows: Battery at armature and make contact of relay DTI, armature |36 and break contact of relay DT4, armature |31 and break contact of relay DTZ, armature |38 and break contact of relay DT3, break contact and armature |39 of relay DT5, conductor 2 of cable 9| and thence to contact |4| associated with armature |42 of relay P2. A circuit is also closed from battery at armature |35 and.

make contact of relay DTI, armature |36 and break contact of relay DT4, armature |43 and break contact of relay DTZ, armature |44. and break contact of relay DT3, break contact and armature |45 of relay DT5, conductor I of cable 9| to contact |46 associated with armature |41 of relay PI. Armature |41 of relay PI and armature |42 of relay P2, are connected together by conductor 93.

When brush DBI engages segment 28 of the ring RI of the distributor DR2, relay PI operates and" applies battery at its contact |46 by way of its armature |41 to' conductor 93, make contact and armature 94 `of relay TIME, conductor 95, winding of indicator TTB, conductor 3 of cable |34, contact |30 of relay G3, con-1 ductor 3 of cable |24, armature |20 and make contact of relay AG to ground thereby causing indicator TTB to be actuated in response to the rst actuation impulse received. As the distrib-- `conductor 93 to operate the indicator 'IT8 over the circuit just described. vAs the brush moves oil.' of segment 28 relay P2 releases and inter--v rupts the circuit to indicator TT8 causing the indicator to step ahead to display the digit 2.

As segment of the ring Rl is engaged by Athe brush DBI, relay P2 again operates causing pulses are transmitted to this indicator as the distributor continues its operation for the reason lease of relay RI releases the relay TIME. The operation of relay REL at its armature 39 removes ground from conductor A38 thereby releasbrush in contact with segment I of ring RI.

thatbattery is applied to conductors I and 2 f conductors I and 3 of cable |0I extending to contacts |40 and |48 of relays PI and P4 respectively. Since the relays .DU are identical with the relays DT, the circuit to their contacts will be described by reference to relays DT as, for example, the circuit to conductor I of relay |0| is as follows: Battery at armature |35 of relay DUI and break contact thereof, armature |49 and break contact of relay DUZ, armature |5| and break contact of relay DU3, armature |52 and break contact of relay DU4, make contact and armature of relay DUS, conductor I of cable |0I and thence to contact I 40 of relay PI. The circuit to conductor 3 of cable IOI may be traced from battery at armature`|53 and break contact of relay DUI, armature |54 and break contact of relay DU2, armature |55 and break contact of relay DU3, armature |56 and make contact of relay DU5, armature |51 and break contact of relay DU4, conductor 3 of cable |0| and thence to contact |48 of relay P4. The operation of relay PI in response to the engagement of seg-` ing relays TC, GAB and G8. As the brush DBI passes off segment 45 of the ring RI, relay REL releases. Thev distributor brush DB1 continues'v to rotate until arrested by the latch 8| with the The time indicators corresponding to flight .number 34 now post the number 35 corresponding to the time when the passage of the aircraft identified as ight 34 is scheduled to pass over the Camden marker.

The distributors DRI and DR2 have each completed one revolution and the information corresponding to the incoming signals controlling this portion of the flight message has been printed by the multiplex printer. The seeker switch, however, is not released at this time, relay L remaining locked to ground at the break contact and armature 23 of relay RS5, which does not operate until the end-of-message signal has passed through the tape transmitter.

With the brush DBI resting on segment of closed from grounded ,ring R2, brush DBI, segment I of ring RI, conductor 35, winding of start magnet SMI of the distributor DRI, conductor 34, wiper and terminal 3 of level C of the seeker switch, conductor 32, winding I of relay TC, conductor 3|, make `contact and armature 29 of relay L to battery, thus causing the operation of relay TC and the start magnet SMI. The operation of start magnet SMI attracts the latch 4| and 'sets the distributor DRI into operation. As the Aeven-numbered segments 2 to I2 of rings RI, R3, R5, R1 and R9 are traversed by their respective brushes, theight identication number 34, x I, altitude range 2 and the altitude digits 45 are stored in the decoding relays of Fig. 5 and printed on. the monitor printer, the

` printing and tape steppingoperations vbeing conat contact |48 and armature |59 of relay P4 to conductor |03 to step the indicator TU8 ahead to display the digit 2. As the distributor brush DBI passes over segments 35, 31 and 39, three additional impulses are applied by the relay P4 to the conductor |03 to cause`the indicator TU8 to step ahead to display the digit 5. As the thereby causing the operation of the release relay REL. lThe operation of relay REL at its armature |I1 removes ground from conductor of cable 41, thereby releasing relay AG. Relay RELat its armature 48 removes battery from conductor 2 of cable 41^thereby releasing the storage and decoding relays of Fig. 5. The retrolled by the passage of the brush B6 overthe even-numbered Segments 2 to I2 of ring RII. The engagement of segment I2 of ring RI I by the 'brush B6 causes the end-of-message signal to be stepped into the tape transmitter 'I'IRI 'I'his signal, it will be recalled, has the code units 3 and 5 thereof marking and the code units I, 2 and 4 spacing in character.

The transmitter tongues I, 2, 3, 4 and 5 are connected by way of conductors I, 2, 3, 4 and 5 of 'cable |62 to the windings of' seeker release relays RSI, RSZ, RS3 and RS4. With theendfof-message' signal in position within the tape transmitter 'ITRL battery isv connected to conductors 3 and 5 of cable |62 thereby operating the seeker-release relays RS'2 and RS4 and applying battery to the winding of relay RS5.

As the distributor brushes engage segments 2| of rings RI and R3, relay GA8 operates Aand locks by lway o f its contacts 16 to ground at the break contact and armature 39 of relay REL.

The range signal ALT having the code units I,

2 and 5 'thereof marking and the code units 3.

and 4 spacing in character causes the operation of relays R|, R2 and R5. A circuit is completed from grounded armature 83 of relay RI, armature 84 and make contact of relay R2, armature |63 and break contact of relay R3, armature |64 and break contact of relay R4, armature |65 and make contact of relay R5, conductor 5 of cable 88, Winding of relay ALT to battery, causing the range selection relay ALT'to opate and close,

lindicaby the latch 4| at the completion oftheirrevolu tion, the start magnet SMI associated therewith having released as the brush DBI of the distribu- ,4 tor DRZ passes off segment I of ring RI.

As the brush DBI engages segments 2 and 23 of the ring RL'relay ST operates but performs no -useful function at this time. When brush DBI traverses segments 4 of the ring RI, relay P1 operates to transmit the first restoration impulse to the selected indicatorsover the following circuit: Battery at armature 89 and break contact of relay AG, conductor `4 of cable 9|, make contact and armature 92 ofrelay P1, conductor 93, make contact and armature |66 of relay ALT, conductor |61, winding of indicator AT8, and switch contact |68 thereof, conductor 5 of cable 91, contacts |69 of relay GA8" to ground. Battery at armature 99 and break contact of relay AG, conductor 4 of cable |0,|, make contact and armature |02 of relay P1, conductor |03, make contact and armature` |1| of relay ALT, conductor |12, Winding of indicator unit AU8 and switch contact |13 thereof, conductor 6 of cable 91, contacts |14 of relay GAS to ground. As the evennumbered segments 4 to 22 of ring RI are traversed by the brush DBI; ten restoration impulses are transmitted to the indicators ATB and AUS to restore them to their blank settings.

As brush DBI engaged segment of the ring Rl, ground was applied to conductor of cable |09, extending to the winding of the seeker release relay RSS from whence the circuit is continued by way of make contact and armature |15 of relay RS4, break contact and armature |16 of relay RS3', make contact and armature |11 of relay RS2, break contact and armature |18 of relay RSI to battery, thereby causing relay RSS to operate and at armature 23 thereof remove ground from conductor 22 causing relay L to release. The release of relay L at its armature 21 removes ground from armature 21 of relays K, RI and R2 i and its break contact closes a circuit from arma- SSM to different positions in accordance withV complete message information stored on any of the perforated tapes of Fig. 1 or the keyset of Fig. 2. When relay L releases the seeker switch is not stepped ahead but remains with the'wipers thereof in contact with their terminals 3 until another complete message has been received.

When brush DBI engages segment 1 of ring Ri, relay PTR operates and applies battery to conductor 2 of cable |09, thereby printing the end-of-message signal by the operation of the print magnet PM of the multiplex printer and stepping the tape ahead by the operation of the tap-e step magnet TM of the tape transmitter TTRI.

When segment i3 of the ring RI is engaged by the brush DBI, relay SP operates and applies battery to the selection magnet SM3 of the printer to store the space signal therein. As brush DBI engages `segment I5 of the ring Rl, relay PTR operates causing the space signal stored in the monitor,y printer to be included in the printed record oi.' the message, the tape step magnet TS operating at this time.

When segment 24 of the ring RI is engaged by the brush DBI, relay AG operates and at the armatures 8,9 and 99 thereof removes battery from conductors 4 of cables 9| and |0| respectively. Relay AG also closes ground to the windings of indicators AT8 and AU8, ground having been removed from the windings of these indicators by the operation of their associated switch contacts |63 and |13 respectivelywhich were opened as the indicators moved into their blank positions.4 Relay AG at armature |25 thereof causes relay G8 to operate thereby completing the ground circuit just described.

The digits 4 and 5 are stored in the first and second digit storage relays of Fig. 5 respectively, relays DTZ and DT4 of the 'first digit storage group and relay DU5 of the second digit storage group being operated. A circuit is` closed from battery at armature |19 and break contact of relay DTI, armature |8| and make contact of relay DTZ, armature |82 and break contact of relay DT3, armature |83 and make contact of contact and armature |66 of relay ALT, conductor |61, winding of indicator AT8, conductor 5 of cable |34, contact |32 of relay G8, conductor 5 of cable |24, armature |22 and make contact of relay AG to ground. As the brush DBI engages segments 33, 35,31 and 39 of the ring RI, relay P4 operates and transmits four impulsesover the circuit just described thereby stepping the tens digit altitude indicator ATB ahead to `display the digit 4. i.

A circuit is closed from battery at armature |35 and break contact of relay DUI. armature |49 and break contact of relay DU2, armature |5| and break contact of relay DU3, armature |52 and break contact of relay DU4, make contact and armature |45 of relay DUE, conductor I of cable IOI, make contact |40 and armature |58 of relay PI, conductor |03, make contact and armature |1| of relay ALT, conductor |12, Winding of indicator AU8, conductor 6 of cable |34, contact |33 of relay G8, conductor 6 of cable |24, armature |23 and make contact of relay AG to ground. As brush DBI passes over segment 26 of the ring RI relay P| operates and transmits the first actuation impulse to the indicator AU8 thereby stepping the indicator AUB ahead to display the digit iA `circuit is closed from battery at armature |53 and break contact of relay DUI, armature |54 and break contact of relay DU2, armature |55 and break contact of relay DU3, armature |56 and make contact of relay DUS, armature |51 and break contact of relay DU4, conductor 3 of cable |0I, contact |48 and armature |59 of relay P4, conductor |03 and thence by way'of make contact and armature |1| of relay ALT and conductor |12 to the gading of the indicator unit AU8, conductor 5 odcable |34, contacts |33 of relay G8, conductor 6 of cable |24 to ground at armature. |23 of relay AG. As the distributor brush DBI engages segments 33, 35, 31 and 39 of the ring RI, relay P4 operates to transmit four additional actuation impulses to the indicator AU8, thereby stepping the indicator AUB ahead to display the digit 5. The digits 4 and 5 are now displayed on the indicators ATBand AUB respectively and the information that flight 34 is sched- 

